you sound a lot like me in a way, just starting out and wanting to make a bit of cash to sort of justify all the time and money you've poured into it.
trying to keep it short, some ideas i've had, and advice i've been given for sales:
- local art groups, see if they do exhibitions you can put one or two shots in.
- country markets and such, sell them from your car boot. downside is you need to invest a lot in printing to sell only a few. can be a fun experience though
- competitions are good, can get your name out there, if you're in their expo some will let you put a 'for sale' sign under the shot, or a bucket of business cards.
- ask a few local cafes and restaurants if they'll hang your stuff for free, with a 'for sale' sign underneath. scope out their decor and offer them something that suits the colour/style of the place.
- in general, nothing gets sold without advertising. handing out business cards has been said, and word of mouth only goes so far. giving out some free is always a good advertising, if you can work it properly.
as for the photos:
- quality vs quantity. I've been told this a lot. you might have a real gem in your portfolio, but people get bored looking through all the mediocre ones on the way there and give up (trust me, i know. i must have uploaded a few thousand to facebook when i was travelling. wasn't trying to sell any, just showing to friends. still, i doubt many people ever looked at them besides if they got tagged in some).
- i love animals too. but anyone can take stuff in a zoo. if they see photos in a folder marked 'zoo', they can think 'ah, i can take that too' and they head off to the zoo with their own camera and you get nothing. take the tigers in the snow photos. if you didn't tell people that was in a zoo, they might imagine some snow-covered area in north india, think 'i can never go there' and buy the pic because they can't make it themselves (or maybe that's how i'd think at least)
- you need to have the 'je ne sais quoi' shots. for me in your pics, it's the blue bird nicely framed by the tree, looking at the camera, with a "what you doin'?" expression. it was a lucky shot for the expression surely, and it's the expression that makes the shot. out of all of them, that'd be the one i'd be most inclined to buy (but sorry, i just don't buy)
- in general, it's the expressions of animals i like (maybe it's just me though?). two tigers play-fighting makes a more emotive photo for someone who has a close sibling, a bird feed a baby might mean more to someone who's just had a kid of their own, a pic of a bowerbird in his nice nest might make a good housewarming present for someone who's just bought their first house. that kind of thing.
in general, good start, more power to you for asking for the help and critique, and good luck to all of us...